Awards

Memberships

Professional Engineers of Ontario
Association of Environmental Engineering and Science Professors (AEESP)
American Society for Microbiology
American Chemical Society

Research Interests

Anaerobic Microbial Community Analysis

These are very exciting times in fundamental and applied environmental microbiology owing to recent advances in analytical tools and techniques to interrogate complex biological systems. These tools include affordable large-scale sequencing, quantitative DNA and RNA extraction and amplification tools, and proteomic analyses applicable to complex mixtures and small sample sizes. These techniques are enabling novel approaches to uncover fundamental metabolism, regulation, genetics, and interspecies metabolite transfer in complex microbial systems of global importance, such as nutrient cycling, wastewater treatment and the human microbiome. Specific applications related to my own research include biomethane production, wastewater treatment, and soil and groundwater bioremediation. These processes rely on complex microbial communities that have defied traditional reductionist microbiological approaches. My research group is actively engaged in research to understand functional interactions in complex microbial consortia, and how these interactions enable much greater activity in the whole as compared to the sum of the individual parts. We have also been very active at translating such knowledge to practice, particularly in the bioremediation field.

Biodegradation, Biotransformation and Bioremediation

My research group focuses on developing an understanding of how biological processes affect the fate of pollutants in the environment. We apply a wide variety of techniques from analytical chemistry, molecular biology, microbiology, enzymology, environmental genomics and proteomics in conjunction with mass and energy balance approaches to unravel and model complex microbial processes, particularly those that occur in anaerobic environments.

Monoaromatic hydrocarbons (such as benzene, toluene and xylene) are prevalent groundwater contaminants as they are found in most petroleum products. These compounds can be biodegraded under a variety of different conditions both aerobically and anaerobically. Anaerobic processes have significant advantages over aerobic processes for in situ bioremediation (i.e., bioremediation in-place in the subsurface) because anaerobic processes are not limited by the availability of oxygen. My research has explored the biological processes that affect the fate of monoaromatic hydrocarbons in anaerobic environments, including detailed characterization of the microbes that catalyze these reactions and their potential role in site remediation.

Chlorinated solvents are widespread groundwater contaminants in all industrialized regions. These solvents are used extensively as degreasing agents and in dry-cleaning. In the presence of oxygen, these compounds are quite stable. However under reduced conditions, they are susceptible to sequential dechlorination ultimately yielding non-chlorinated (non-toxic) products. Microbes naturally present in the environment are responsible for the reductive dehalogenation of many chlorinated solvents. My laboratory has been actively engaged in translating this knowledge to practice for bioremediation and in particular bioaugmentation, taking advantage of the unique metabolism of these fascinating anaerobic microbes that “breathe” chlorinated solvents.

Anaerobic Digestion of Industrial and Municipal wastes

Anaerobic digestion of organic waste has tremendous potential to address the economic and the environmental pressures facing most industries and municipalities. While anaerobic digestion is widely applied already in certain sectors, there is keen interest to expand its use to new waste streams, for example in the pulp and paper industry. Using a combination of pre-treatment methods and reactor configurations, combined with new molecular and analytical tools to gain mechanistic information on anaerobic processes, we are investigating alternative approaches to recover energy from waste liquid and solid streams.